1. Technical Field
Several aspects of the present invention relate to a method for manufacturing an electro-optical device and also relates to an electronic apparatus.
2. Related Art
Electrophoretic displays have been known as electro-optical devices and each contain an electrophoretic dispersion which is a display material having optical properties varied by electrical stimulation which contains a liquid dispersion medium and electrophoretic particles. The application of an electric field to the electrophoretic dispersion varies the distribution of the electrophoretic particles to vary optical properties of the electrophoretic dispersion.
The electrophoretic displays require no backlights; hence, the electrophoretic displays can be manufactured at low cost and have a reduced thickness. Furthermore, the electrophoretic displays have a wide viewing angle, a high contrast ratio, and a function of holding a displayed image. Therefore, the electrophoretic displays are attracting much attention as next-generation display devices.
Some of the electrophoretic displays each include a transparent substrate having a transparent common electrode; a substrate having pixel electrodes; and microcapsules, sandwiched between these substrates, containing the electrophoretic dispersion.
The electrophoretic dispersion is sealed in the microcapsules. Therefore, the electrophoretic dispersion can be prevented from leaking out of the microcapsules during the manufacture of the electrophoretic displays and the electrophoretic particles can be prevented from precipitating or aggregating. These substrates are made of plastic or the like in view of flexibility, cracking resistance, and weight reduction. In recent years, the microcapsulation of dispersions has been widely used.
JP-A-64-86116 discloses an electrophoretic display including a pair of substrates and microcapsules containing a dispersion containing electrophoretic particles, at least one the substrates being transparent, the microcapsules being sandwiched between the substrates.
JP-A-10-149118 discloses an electrophoretic display including a transparent substrate, an opaque rear substrate opposed to the transparent substrate, and a large number of microcapsules. These substrates have opposed faces having transparent electrodes. The microcapsules are placed in closed spaces present between the transparent electrodes.
The microcapsulation of dispersions facilitates the sealing treatment of the dispersions and is useful in obtaining good images.
In recent years, it has been proposed that the electrophoretic displays are used in a curved state. FIG. 8 shows a conventional curved electrophoretic display 70. In a method for manufacturing the electrophoretic display 70, a display 72 sealed between a pair of protective films 71 and 71′ is directly bent and therefore the residual stress caused by bending is applied to a sealing section 73. This causes the protective film 71′ to be released from an inner substrate 74, covered with the protective film 71′, having a small radius of curvature or to be wrinkled. Although the protective film 71′ is initially bonded tightly to the inner substrate 74, the protective film 71′ is released from the inner substrate 74 or wrinkled while the protective film 71′ is used for a long time in a curved state. The tension of the protective film 71′ bonded to the inner substrate 74 is reduced by bending; hence, the protective film 71′ has released portions or wrinkles. The released portions or wrinkles cause cracks, which cause problems such as the deterioration of water resistance. This can cause display failure or other problems; hence, long-term reliability cannot be assured.